title: The mean values of liver stiffness assessed by Acoustic Radiation Force Impulse elastography in normal subjects.
abstract: The AIM of this paper is to establish the values of liver stiffness (LS) assessed by means of ARFI in patients without known liver pathology and considered healthy subjects.
  
  
  METHODS
  the study group was composed of 82 subjects without known liver pathology, healthy volunteers or patients from other departments of our hospital who did not have altered liver laboratory tests. 76 patients had ARFI valid measurements (47 women and 29 men, mean age 34.5 +/-14.3 years). In each subject abdominal ultrasound was performed (patients with steatosis or any other signs of chronic liver pathology were excluded) as well as ARFI (using Siemens Acuson S2000). The median value of 10 measurements was calculated, expressed in m/s; we considered valid only the measurements with IQR<30%, SR>60%, similar to transient elastography. Mean ARFI values and mean values according to age and gender were evaluated.
  
  
  RESULTS
  valid ARFI measurements were obtained in 76/82 patients (92.6%). The mean value of ARFI measurements in normal individuals was 1.15+/-0.21 m/s. There were no significant differences between the mean ARFI values in men vs. women (1.16+/-0.21 vs. 1.14+/-0.22m/s, p=0.67), also among different age groups (p>0.05).
  
  
  CONCLUSIONS
  In our study the mean LS value obtained by ARFI in healthy subjects was 1.15 m/s.
authors.affiliation: Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy Victor Babes, Barbu Iscovescu str. 8, 300561, Timisoara, Romania. alinamircea.popescu@gmail.com
authors.forename: Alina
authors.initials: A
authors.lastname: Popescu
authors.forename: Ioan
authors.initials: I
authors.lastname: Sporea
authors.forename: Roxana
authors.initials: R
authors.lastname: Sirli
authors.forename: Simona
authors.initials: S
authors.lastname: Bota
authors.forename: Mircea
authors.initials: M
authors.lastname: Focşa
authors.forename: Mirela
authors.initials: M
authors.lastname: Dănilă
authors.forename: Diana
authors.initials: D
authors.lastname: Nicoliţă
authors.forename: Alina
authors.initials: A
authors.lastname: Martie
authors.forename: Mădălina
authors.initials: M
authors.lastname: Sendroiu
authors.forename: Ana
authors.initials: A
authors.lastname: Juchiş
mesh_terms: D000328:Adult; D055119:Elastic Modulus / Q000502:physiology; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008099:Liver / Q000000981:diagnostic imaging* / Q000502:physiology*; D008297:Male; D012016:Reference Values; D012680:Sensitivity and Specificity